In medical testing and processing, the use of robotics may minimize exposure to, or contact with, bodily fluid samples (otherwise referred to as “specimens”) and/or may significantly increase productivity. For example, in some automated testing and processing systems (e.g., clinical analyzers), a specimen and/or reagent liquid may be aspirated from one liquid-containing vessel and may be transferred to another liquid-containing vessel (e.g., a reaction cuvette, etc.).
Such liquid transfer may be accomplished by the use of a robotic mechanism, which may include a suitable moveable robotic component and an attached probe. The probe may be moved in one or more coordinate directions by the robotic component. In this manner, the probe may aspirate a specimen or reagent liquid from a first liquid-containing vessel, and then move and dispense the specimen or reagent liquid into another liquid-containing vessel.
During the aspiration step, it is desirable to check/verify whether a correct volume of the specimen or reagent liquid has indeed been aspirated. Accordingly, conventional systems may include a pressure sensor that is used to monitor a representative aspiration pressure as the specimen or reagent liquid is being aspirated. Furthermore, such conventional systems may undergo a calibration step to calibrate the pressure sensor by aspirating a liquid (e.g., a reagent liquid) in order to establish a baseline reference value against which other pressure readings taken during the testing will be compared.
Notably, however, inaccuracies in the calibration may result in inaccurate judgment being made about whether, for example, a sufficient amount of the specimen or reagent liquid has in fact been aspirated. Thus, accurate calibration may be important to improve accuracy of testing results. When the size (e.g., volume) of the specimen or liquid reagent being aspirated is relatively small, proper calibration becomes especially important.
Accordingly, methods and systems that may improve an accuracy or reliability of liquid aspiration are desired.